The present invention generally relates to fluid couplings and, more particularly, to fittings used on flexible hoses such as common garden hoses used for carrying liquids.
Hose fittings of the above-mentioned type are used at the open end of a flexible hose to connect the hose in a fluid tight manner to other fittings, faucets, spray devices or other objects. In the past these fittings have been formed of materials such as metal alloys which allow the fitting to be permanently secured to the hose by swaging or otherwise deforming tubular portions of the fitting onto the end of the hose. Such metallic hose fittings are relatively expensive to manufacture and often corrode due to their constant contact with various liquids.
Hose fittings have been developed in the past which utilize an inner tubular component and an outer tubular component to compress the hose therebetween and secure the fitting in a fluid tight manner to the end of the hose. Examples of such fittings are found in U.S. Pat. No. 3,177,016 to Holmgren, U.S. Pat. No. 3,788,676 to Lossie and U.S. Pat. No. 4,736,969 to Fouts. Each of the fittings disclosed in these patents suffers from the disadvantage that there is no positive, irreversible locking mechanism for permanently establishing a fluid tight seal between the fitting and the hose. That is, each of these patents disclose two piece fittings wherein two components of the fitting are threadingly secured together in order to compress the hose therebetween. Since the two components are threaded together, they may also become unthreaded with respect to each other and thereby lose their fluid tight seal with the hose.
U.S. Pat. No. 3,902,745 to Mooney et al. discloses an electrical connector for providing an hermetic coupling with a flexible electrical conduit of the type having an external liquid and gas proof sheath of resilient material surrounding a helically wound flexible metallic core provided with an internal helical channel. Mooney et al. disclose the use of an annular channel formed in an outer end face of a locking collar which registers with outer projections on the tubular component which threads into the electrical conduit. However, this locking mechanism suffers from the disadvantage that it requires that the locking collar to be formed of a polymeric material while the tubular component and its projections are formed of a metallic material thus increasing the cost of the fitting as well as its susceptibility to corrosion. Moreover, this electrical connector is designed specifically for use with electrical conduits having an inner core in the form a spirally wound metallic strip. This electrical connector therefore would be impossible to use on a fluid carrying flexible hose.
In view of the shortcomings of the prior art, there is a need in the art for a hose fitting which may be formed entirely of relatively inexpensive polymeric material and which further includes means for positively and permanently securing the hose fitting to an open end of a hose in a fluid tight manner.